The present invention relates to venting tape, and in particular to venting tape used to vent an enclosed article space to be filled with an expandable foam material.
Injected expandable foam materials are used to insulate numerous articles in a wide variety of applications, such as refrigerators, freezers, and the like. The expandable foam material is typically injected into the walls of the appliances between an outer housing and an inner casing, thereby providing a uniform thermal barrier therebetween.
The outer housing of these appliances are typically provided with holes and apertures for venting purposes during the injection of the foam material. These "vent holes" allow the manufacturer to provide an air-tight seal between the outer housing and the inner casing, while allowing air/gas to escape as the expandable foam fills the void therebetween. These holes must be temporary covered during the foam injection process to prevent the foam from escaping from between the inner casing and the outer housing. Heretofore, manufacturers have used foam pads to plug the holes. The pads are designed to allow gas to escape as the foam expands yet restricting the flow of foam through the holes. These pads must be specially cut and formed for each application thereby significantly adding to the cost of manufacture. Further, these pads are often difficult to install during the manufacturing process. In addition, the foam pads typically are supplied in the form of a large coil that is cumbersome to handle and control. Porous tapes have also been used to plug the holes. Several problems have been associated with these tapes including inadequate strength resulting in foam leakage, as well as inadequate air/gas flow resulting in non uniform fill of the injected foam within the appliance. In addition, porous tapes often tear when the expandable foam actually contacts the tape, thereby allowing the foam to escape from within the appliance. Improper venting is often caused by the adhesives associated with the tapes plugging the holes therein and disrupting the air flow therethrough.